Mbh 3.95.1a

Vaisampayana said, “The heroic sons of Pandu, accompanied by their followers, proceeding from place to place, at last arrived at Naimisha. O king, reaching the Gomati, the Pandavas bathed in the sacred tirtha of that stream, and having performed their ablutions there, they gave away, O Bharata, both kine and wealth! And repeatedly offering oblations of water, O Bharata, to the gods, the pitris, and the Brahmanas, in the tirthas called Kanya, Aswa, and Go and staying (as directed) in Kalakoti and the Vishaprastha hills, the Kauravas then, O king, reached Vahuda and performed their ablution in that stream. Proceeding next, O lord of earth, to the sacrificial region of the gods known by the name Prayaga, they bathed in the confluence of Ganga and Yamuna and residing there practised ascetic penances of great merit. And the Pandavas, of truthful promises, bathing in the tirtha, cleansed themselves of every sin. The sons of Pandu then, O king of the Bharata race, accompanied by those Brahmanas, proceeded to the tirtha called Vedi, sacred to the Creator and adored by the ascetics. Residing there for some time and gratifying the Brahmanas with the fruit and roots of the wilderness and clarified butter, those heroes began to practise ascetic penances of great merit. They then proceeded to Mahidhara consecrated by that virtuous royal sage Gaya of unrivalled splendour. In that region is the hill called Gayasira, as well as the delightful river called Mahanadi, with fine banks graced by bushes of canes. On that celestial hill of holy peaks is a sacred tirtha called Brahmasara which is much adored by ascetics. There on the banks of that lake had dwelt of yore the eternal god himself of justice, and it was thither that the illustrious Rishi Agastya had repaired to behold that deity. It is from that lake that all the rivers take their rise and there in that tirtha, Mahadeva the wielder of the Pinaka, is present for aye.